#include <iostream>
#include <string>
using namespace std;

int simple(int n){
    int d = 0;
    for (int i = 1; i<= n; i++)
        if (n % i == 0) d++;
    if (d == 2) return n;
    return 0;
}


int main(){

    string text;
    getline(cin, text);
//
    int pr=0;
    for (int i=0; i < text.size(); i++)
        if (text[i] == ' ')
            pr++;

    string slova[pr+1];
    string word;


    int k = 0;
    for (int i=0; i < text.size(); i++){
        if (text[i] == ' '){
            slova[k] = word;
            word = "";
            k++;
        }
        else word += text[i];
    }
      slova[k] = word;

    int s = 0, d = 0, e = 0;
    if (slova[0] == "one") s =1;
    if (slova[0] == "two") s =2;
    if (slova[0] == "three") s =3;
    if (slova[0] == "four") s =4;
    if (slova[0] == "five") s =5;
    if (slova[0] == "six") s =6;
    if (slova[0] == "seven") s =7;
    if (slova[0] == "eight") s =8;
    if (slova[0] == "nine") s =9;
    if (slova[0] == "zero") s =0;

    if (slova[1] == "one") d =1;
    if (slova[1] == "two") d =2;
    if (slova[1] == "three") d =3;
    if (slova[1] == "four") d =4;
    if (slova[1] == "five") d =5;
    if (slova[1] == "six") d =6;
    if (slova[1] == "seven") d =7;
    if (slova[1] == "eight") d =8;
    if (slova[1] == "nine") d =9;
    if (slova[1] == "zero") d =0;

    if (slova[2] == "one") e =1;
    if (slova[2] == "two") e =2;
    if (slova[2] == "three") e =3;
    if (slova[2] == "four") e =4;
    if (slova[2] == "five") e =5;
    if (slova[2] == "six") e =6;
    if (slova[2] == "seven") e =7;
    if (slova[2] == "eight") e =8;
    if (slova[2] == "nine") e =9;
    if (slova[2] == "zero") e =0;
    int n = s * 100 + d * 10 + e;

    cout<<simple(n);
}
